tan colored oil on oild cap?

I was changing my oil today and noticed some tan colored sunstance on the inside of my oil fill cap. It looked like what you see at the top of an expresso. Does anyone know what this is? I afraid that it could sludge?

Usually just condensation mixed with oil it makes that pasty looking goo.wipe it off and a good long run at hway speeds should keep it clear.when you change your oil make sure the oil does not look like that,if so time to check head gasket.
probably just the condensation goo tho!!
ohlord

I agree with the above, if the tan colored espresso mix is on the inside of the filler cap it is from condensation. If the oil on the dip stick looks the same that is usually bad.

thanks for the advice guys!! I have another question...when should the timing belt be changed??

1998 ,it is a chain,proper oil changes with the correct fleece filter and mobil 1 0w40 syn oil at the proper intervals and the chain should last over 200k.
ohlord
filters at        www.autohausaz.com
oil change diy on
http://www.mercedesshop.com/Wikka/DoItYourSelf

thanks, I ordered up some oil and filters. Hey, I was wondering if anyone knows a trick to fix the foggy headlight problem that is common on high mileage E320's? any polishing? mine are pretty bad...do I need to buy new lenses?

Search my post on benzworld.org on headlight polishing,if you can't find it pm me and I will try to find or write you up a how to.They come out new looking and with   h7 65watt rally bulbs from 
www.danielsternlighting.com
they will look like flame throwers.
ohlord

didnt find the info on the headlight polishing...any help would be appreciated!! thanks.